Street Cup Idle Weak And Losing Power In Midrange

Hello!

I've been slowly going through post winter (and presale) checks with my bike over the last month, including checking pipes and wiring ect are sound, and changing the spark plugs along with putting in new, premium fuel, however, unfortunately my 2016 Street Cup is still riding sluggish.

Especially when idle, the bike seems to be fluctuating from 500-1,500rpm, and every now and then will suddenly spike to 2/2.5k. This idle issue has caused the bike to cut out at lights and even when just at the side of the road when allowing it to warm up prior to a ride.

Yesterday when out for a 2 hour ride, I noticed at round 50mph in 3rd, the bike began to lose power. It wasn't doing this all day, and didn't do it after, however, it required me to lay off the throttle and drop to second to regain power.

Additionally, the bike (especially before changing plugs) would find it difficult to pull away and I needed to give more throttle to get the bike to rev. Though this isn't the case anymore, I thought it would be helpful trouble shooting info!

From what I've read up, I believe the bike maybe starved of air and have ordered a new air filter (though I haven't checked the current one, I just wanted to ensure it was fresh). Though, I wanted to see if any more experienced riders have any other ideas that could be causing this sluggish riding.

Hope this is all helpful information and thank you for any helpful ideas and insight! I'll be sure to keep everyone updated on the progress!

P.S. I am not running stock pipes. Not sure if this will make an enormous difference but they are Motone Custom Shotgun pipes and have been on the bike since I purchaced back in Sep 2022. I have also ran the bike using stock pipes for a short while and other than noise difference, I didn't notice a change in power while they were installed.

 

Thank you, I'll have a look over now the air filter has arrived.

 

After fitting the new air filter and taking it for a ride, the bike seemed like it was riding properly again. However, once the bike had fully warmed up, the issues started all over again.